1. Field of the Invention
The present invention relates in general to distributed control systems for heavy construction machines, and more particularly to a distributed control system for a heavy construction machine which is capable of controlling electric and electronic components in the heavy construction machine in a decentralized manner such that in a decentralized manner such that the control system transmit and receive data through respective communication lines.
2. Description of the Prior Art
Generally, a heavy construction machine is equipped with a plurality of sensors for transmitting signals to a controller or an indication unit through lines or connectors. As the sensors are increased in number, the mechanical reliability of the heavy construction machine is reduced.
Further, the number of sensors is necessarily increased still more as the heavy construction machine is sort to be enhanced in performance. The increased number of sensors results in an increase in the number of wires, which in turn results in an increase in the cost.
A distributed control system is used in a heavy construction machine to perform a fault diagnostic operation for the heavy construction machine at once on the spot. As a result of the fault diagnostic operation, the heavy construction machine may be repaired by simply replacing a faulty module with a new one. In this manner, the planned operation of the heavy construction machine is hardly frustrated.
The distributed control system has a self-diagnostic function for each of the modules and allows the modules to exchange desired information among them. In this light, it can be seen that the distributed control system is an essential, required element required for individual control operations in construction machines, vehicles, ships, airplanes and etc. in which operation/maintenance must readily be performed.
In a conventional distributed control system for a heavy construction machine, signals corresponding to the chosen operation of an operator are transferred to component controllers through respective lines. Also, signals from various sensors are transferred to a main controller through respective lines.
For these reasons, as the functions of the heavy construction machine become more various, the number of wires is increased, resulting in a difficulty in wiring and increases in load and volume.
The increased number of wires also results in an increase in the number of connectors, thereby making it difficult to recognize the wired state in a terminal. These consideration pose a difficulty in designing the control system for the heavy construction machine.
Further, when a fault is caused due to poor line contact or wire disconnection, the corresponding portion of the control system cannot be readily identified. As a result, the repair, resulting in an increase in consumer's dissatisfaction.